Thin heat pipe structure and manufacturing method thereof

ABSTRACT

A thin heat pipe structure and a manufacturing method thereof. The thin heat pipe structure includes a tubular body and a support body. The tubular body has at least one receiving space in which a working fluid is contained. The support body is disposed in the receiving space to partition the receiving space into a first chamber and a second chamber. By means of the manufacturing method of the thin heat pipe structure, the thin heat pipe structure can be made with greatly enhanced heat transfer efficiency. In addition, in the manufacturing process, the ratio of good products is increased to lower the manufacturing cost.

This application claims the priority benefit of Taiwan patentapplication number 100119071 filed on May 31, 2011.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a thin heat pipe structure and amanufacturing method thereof. By means of the manufacturing method, theheat pipe structure can be made with a thin configuration and enhancedheat transfer efficiency. In addition, in the manufacturing process, theratio of good products is increased.

2. Description of the Related Art

A heat pipe has heat conductivity several times to several tens timesthat of copper, aluminum or the like. Therefore, the heat pipe hasexcellent performance and serves as a cooling component applied tovarious electronic devices. As to the configuration, the conventionalheat pipes can be classified into heat pipes in the form of circulartubes and heat pipes in the form of flat plates. For cooling anelectronic component such as a CPU, preferably a flat-plate heat pipe isused in view of easy installation and larger contact area. To catch upthe trend toward miniaturization of cooling mechanism, the heat pipe hasbecome thinner and thinner in adaptation to the cooling mechanism.

The heat pipe is formed with an internal space as a flow path for theworking fluid contained in the heat pipe. The working fluid is convertedbetween liquid phase and vapor phase through evaporation andcondensation and is transferable within the heat pipe for transferringheat. The heat pipe is formed with sealed voids in which the workingfluid is contained. The working fluid is phase-changeable andtransferable to transfer heat.

The heat pipe is used as a heat conduction member. The heat pipe isfitted through a radiating fin assembly. The working fluid with lowboiling point is filled in the heat pipe. The working fluid absorbs heatfrom a heat-generating electronic component (at the evaporation end) andevaporates into vapor. The vapor goes to the radiating fin assembly andtransfers the heat to the radiating fin assembly (at the condensationend). A cooling fan then carries away the heat to dissipate the heatgenerated by the electronic component.

The heat pipe is manufactured in such a manner that metal powder isfilled into a hollow tubular body and sintered to form a capillarystructure layer on the inner wall face of the tubular body. Then thetubular body is vacuumed and filled with the working fluid and thensealed. On the demand of the electronic equipment for slimconfiguration, the heat pipe must be made with a thin configuration.

In the conventional technique, a hollow tubular body is pressed into aflat-plate form. Then the sintered capillary body is disposed into thehollow tubular body. Then the hollow tubular body is vacuumed and filledwith the working fluid. Finally, the hollow tubular body is sealed.According to such process, the heat pipe can be made with a flatconfiguration. However, when bending or shaping the heat pipe, theinternal sintered capillary body will crack apart or detach from thetubular body. In this case, the heat pipe will become a defectiveproduct.

Alternatively, when manufacturing the thin heat pipe, the powder isfirst filled into the heat pipe and then sintered. Then the heat pipe isflattened. Then the heat pipe is filled with the working fluid andsealed. Alternatively, the tubular body of the heat pipe is firstpressed and flattened and then the powder is filled into the tubularbody and sintered. However, the internal chamber of the tubular body isextremely narrow. Therefore, it is quite hard to fill the powder intothe tubular body. Moreover, the capillary structure in the heat pipeneeds to provide capillary attraction for transferring the working fluidon one hand and support the tubular body on the other hand. The supporteffect is quite limited in such a narrow space.

Furthermore, the vapor passageways in the heat pipe are so narrow thatan effective vapor/liquid circulation can be hardly achieved. Therefore,the conventional thin heat pipe and the manufacturing method thereofhave many defects.

According to the above, the conventional technique has the followingshortcomings:

1. It is hard to process and manufacture the thin heat pipe.2. The capillary structure in the heat pipe is subject to damage.3. The manufacturing cost is higher.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a thin heat pipestructure having a thin configuration and enhanced heat transferefficiency.

A further object of the present invention is to provide a manufacturingmethod of the above thin heat pipe structure.

To achieve the above and other objects, the thin heat pipe structure ofthe present invention includes a tubular body and a support body.

The tubular body has at least one receiving space and a first closed endand a second closed end in communication with the receiving space. Aworking fluid is contained in the receiving space. The support body isdisposed in the receiving space to partition the receiving space into afirst chamber and a second chamber. The first and second chambersaxially extend through the tubular body.

The manufacturing method of the thin heat pipe structure of the presentinvention includes steps of: preparing a tubular body and a supportbody; placing the support body into the tubular body; pressing thetubular body into a flat form; vacuuming the tubular body and filling aworking fluid into the tubular body; and sealing the tubular body.

By means of the manufacturing method of the present invention, the heatpipe structure can be made with a thin configuration and greatlyenhanced heat transfer efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 a is a perspective exploded view of a first embodiment of thethin heat pipe structure of the present invention;

FIG. 1 b is a perspective assembled view of the first embodiment of thethin heat pipe structure of the present invention;

FIG. 2 a is a perspective view of the support body of the firstembodiment of the thin heat pipe structure of the present invention in afirst aspect;

FIG. 2 b is a perspective view of the support body of the firstembodiment of the thin heat pipe structure of the present invention in asecond aspect;

FIG. 2 c is a perspective view of the support body of the firstembodiment of the thin heat pipe structure of the present invention in athird aspect;

FIG. 3 is a sectional view of the tubular body of a second embodiment ofthe thin heat pipe structure of the present invention;

FIG. 4 is a sectional view of the tubular body of a third embodiment ofthe thin heat pipe structure of the present invention;

FIG. 5 a is a sectional view of the tubular body of a fourth embodimentof the thin heat pipe structure of the present invention;

FIG. 5 b is a sectional view of the tubular body of a fifth embodimentof the thin heat pipe structure of the present invention;

FIG. 6 is a sectional view of the tubular body of a sixth embodiment ofthe thin heat pipe structure of the present invention;

FIG. 7 a is a top view of the first capillary structure of the sixthembodiment of the thin heat pipe structure of the present invention;

FIG. 7 b is a top view of the third capillary structure of the sixthembodiment of the thin heat pipe structure of the present invention;

FIG. 8 is a flow chart of a first embodiment of the manufacturing methodof the thin heat pipe structure of the present invention;

FIG. 9 is a flow chart of a second embodiment of the manufacturingmethod of the thin heat pipe structure of the present invention;

FIG. 10 is a flow chart of a third embodiment of the manufacturingmethod of the thin heat pipe structure of the present invention; and

FIG. 11 is a flow chart of a fourth embodiment of the manufacturingmethod of the thin heat pipe structure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 1 a to 2 c. FIG. 1 a is a perspective explodedview of a first embodiment of the thin heat pipe structure of thepresent invention. FIG. 1 b is a perspective assembled view of the firstembodiment of the thin heat pipe structure of the present invention.FIG. 2 a is a perspective view of the support body of the firstembodiment of the thin heat pipe structure of the present invention in afirst aspect. FIG. 2 b is a perspective view of the support body of thefirst embodiment of the thin heat pipe structure of the presentinvention in a second aspect. FIG. 2 c is a perspective view of thesupport body of the first embodiment of the thin heat pipe structure ofthe present invention in a third aspect. The thin heat pipe structure 1includes a tubular body 11 and a support body 12.

The tubular body 11 has at least one receiving space 111 and a firstclosed end 112 and a second closed end 113 in communication with thereceiving space 111. A working fluid 2 is contained in the receivingspace 111 (as shown in FIG. 3).

The support body 12 is disposed in the receiving space 111 and hasmultiple meshes 121. The support body 12 is selected from a groupconsisting of mesh body (as shown in FIG. 2 a), board material havingrecessed/raised sections on its surface (as shown in FIG. 2 b) and wavedboard body (as shown in FIG. 2 c).

Please refer to FIG. 3, which is a sectional view of the tubular body ofa second embodiment of the thin heat pipe structure of the presentinvention. The second embodiment is substantially identical to the firstembodiment in structure and thus will not be repeatedly describedhereinafter. The second embodiment is only different from the firstembodiment in that the second embodiment further includes a firstcapillary structure 13 disposed in the receiving space 111. The firstcapillary structure 13 is attached to one side of the support body 12.The first capillary structure 13 together with the support body 12partitions the receiving space 111 into a first chamber 1111 and asecond chamber 1112. The first and second chambers 1111, 1112 axiallyextend through the tubular body 11.

The first capillary structure 13 is selected from a group consisting ofsintered powder body, a structure with multiple channels, mesh body,fiber body and foam body. In this embodiment, the first capillarystructure 13 is, but not limited to, sintered powder body forillustration purposes only.

Please refer to FIG. 4, which is a sectional view of the tubular body ofa third embodiment of the thin heat pipe structure of the presentinvention. The third embodiment is substantially identical to the firstembodiment in structure and thus will not be repeatedly describedhereinafter. The third embodiment is only different from the firstembodiment in that the third embodiment further includes a firstcapillary structure 13 disposed in the receiving space 111. The firstcapillary structure 13 encloses the support body 12.

Please refer to FIG. 5 a, which is a sectional view of the tubular bodyof a fourth embodiment of the thin heat pipe structure of the presentinvention. The fourth embodiment is substantially identical to the firstembodiment in structure and thus will not be repeatedly describedhereinafter. The fourth embodiment is only different from the firstembodiment in that a second capillary structure 3 is disposed on innerwall face of the tubular body 11. The second capillary structure 3 isselected from a group consisting of sintered powder body and a structurewith multiple channels. In this embodiment, the second capillarystructure 3 is, but not limited to, sintered powder body forillustration purposes only. The powder of the sintered powder body isselected from a group consisting of copper powder and aluminum powder.In this embodiment, the powder of the sintered powder body is, but notlimited to, copper powder for illustration purposes only.

Please refer to FIG. 5 b, which is a sectional view of the tubular bodyof a fifth embodiment of the thin heat pipe structure of the presentinvention. The fifth embodiment is substantially identical to the firstembodiment in structure and thus will not be repeatedly describedhereinafter. The fifth embodiment is only different from the firstembodiment in that a second capillary structure 3 is disposed on innerwall face of the tubular body 11. The second capillary structure 3 isselected from a group consisting of sintered powder body and a structurewith multiple channels. In this embodiment, the second capillarystructure 3 is, but not limited to, a structure with multiple channelsfor illustration purposes only.

Please refer to FIGS. 6, 7 a and 7 b. FIG. 6 is a sectional view of thetubular body of a sixth embodiment of the thin heat pipe structure ofthe present invention. FIG. 7 a is a top view of the first capillarystructure of the sixth embodiment of the thin heat pipe structure of thepresent invention. FIG. 7 b is a top view of the third capillarystructure of the sixth embodiment of the thin heat pipe structure of thepresent invention. The sixth embodiment is substantially identical tothe second embodiment in structure and thus will not be repeatedlydescribed hereinafter. The sixth embodiment is only different from thesecond embodiment in that the sixth embodiment further includes a thirdcapillary structure 14 disposed in the tubular body 11. The thirdcapillary structure 14 is, but not limited to, mesh body forillustration purposes only. The third capillary structure 14 hasmultiple meshes 141 and is attached to the other side of the supportbody 12 opposite to the first capillary structure 13.

The meshes of 141 of the third capillary structure 14 have a size largerthan that of the meshes 121 of the support body 12. Alternatively, themeshes 121 of the support body 12 can be classified into large meshesand small meshes. The large and small meshes are alternately arranged.The meshes 141 of the third capillary structure 14 can be classifiedinto large meshes and small meshes. The large and small meshes arealternately arranged.

Please refer to FIG. 8, which is a flow chart of a first embodiment ofthe manufacturing method of the thin heat pipe structure of the presentinvention. Also referring to FIGS. 1 to 7 b, the manufacturing method ofthe thin heat pipe structure of the present invention includes steps of:

S1: preparing a tubular body and a support body, a hollow tubular body11 with at least one open end and a support body 12 being prepared;S2: placing the support body into the tubular body, the support body 12being placed into the receiving space 111 of the tubular body 11;S3: pressing the tubular body into a flat form, the tubular body 11being pressed into a flat form by means of pressing;S4: vacuuming the tubular body and filling the working fluid into thetubular body, the receiving space 111 of the flattened tubular body 11being vacuumed and filled with the working fluid 2; andS5: sealing the tubular body, the open end of the tubular body 11, whichis vacuumed and filled with the working fluid 2 being sealed.

Please refer to FIG. 9, which is a flow chart of a second embodiment ofthe manufacturing method of the thin heat pipe structure of the presentinvention. Also referring to FIGS. 1 and 7 b, the manufacturing methodof the thin heat pipe structure of the present invention includes stepsof:

S1: preparing a tubular body and a support body;S2: placing the support body into the tubular body;S3: pressing the tubular body into a flat form;S4: vacuuming the tubular body and filling the working fluid into thetubular body; andS5: sealing the tubular body.

The second embodiment of the manufacturing method of the thin heat pipestructure of the present invention is substantially identical to thefirst embodiment and thus will not be repeatedly described hereinafter.The second embodiment is different from the first embodiment in that instep S1, a tubular body and a mesh body are prepared. In addition, afterstep S1, the second embodiment further includes a step S6 of forming asecond capillary structure in the tubular body.

A second capillary structure 3 is formed on the inner wall face of thetubular body 11 by means of sintering. Alternatively, the inner wallface of the tubular body 11 is formed with multiple channels as thecapillary structure.

Please refer to FIG. 10, which is a flow chart of a third embodiment ofthe manufacturing method of the thin heat pipe structure of the presentinvention. Also referring to FIGS. 1 and 7 b, the manufacturing methodof the thin heat pipe structure of the present invention includes stepsof:

S1: preparing a tubular body and a support body;S2: placing the support body into the tubular body;S3: pressing the tubular body into a flat form;S4: vacuuming the tubular body and filling the working fluid into thetubular body; andS5: sealing the tubular body.

The third embodiment of the manufacturing method of the thin heat pipestructure of the present invention is substantially identical to thefirst embodiment and thus will not be repeatedly described hereinafter.The second embodiment is different from the first embodiment in that instep S2, the support body and the first capillary structure are placedinto the tubular body. In addition, after step S2, the third embodimentfurther includes a step S7 of bending the tubular body.

After the support body 12 and the first capillary structure 13 areplaced into the tubular body 11, the tubular body 11 is bent.Thereafter, step S3 of pressing the tubular body into a flat form isperformed.

Please refer to FIG. 11, which is a flow chart of a fourth embodiment ofthe manufacturing method of the thin heat pipe structure of the presentinvention. Also referring to FIGS. 1 and 7 b, the manufacturing methodof the thin heat pipe structure of the present invention includes stepsof:

S1: preparing a tubular body and a support body;S2: placing the support body into the tubular body;S3: pressing the tubular body into a flat form;S4: vacuuming the tubular body and filling the working fluid into thetubular body; andS5: sealing the tubular body.

The fourth embodiment of the manufacturing method of the thin heat pipestructure of the present invention is substantially identical to thefirst embodiment and thus will not be repeatedly described hereinafter.The fourth embodiment is different from the first embodiment in thatafter step S1 of preparing a tubular body and a support body, the fourthembodiment further includes a step S8 of preparing a first capillarystructure and fixedly attaching the first capillary structure to thesupport body.

A first capillary structure 13 is prepared and fixedly attached to thesupport body 12. The first capillary structure 13 can be attached to oneside of the support body 12. Alternatively, the first capillarystructure 13 encloses the support body 12. The first capillary structure13 is fixedly attached to the support body 12 by means of a measureselected from a group consisting of spot welding, diffusion bonding andultrasonic welding.

The above embodiments are only used to illustrate the present invention,not intended to limit the scope thereof. It is understood that manychanges and modifications of the above embodiments can be made withoutdeparting from the spirit of the present invention. The scope of thepresent invention is limited only by the appended claims.

1. A thin heat pipe structure comprising: a tubular body having at leastone receiving space and a first closed end and a second closed end incommunication with the receiving space, a working fluid being containedin the receiving space; and a support body disposed in the receivingspace to partition the receiving space into a first chamber and a secondchamber, the first and second chambers axially extending through thetubular body.
 2. The thin heat pipe structure as claimed in claim 1,further comprising a first capillary structure disposed in the receivingspace and attached to the support body, the first capillary structuretogether with the support body partitioning the receiving space into thefirst and second chambers.
 3. The thin heat pipe structure as claimed inclaim 1, wherein the tubular body has a flat form.
 4. The thin heat pipestructure as claimed in claim 2, wherein the first capillary structureis selected from a group consisting of sintered powder body, mesh body,fiber body and foam body.
 5. The thin heat pipe structure as claimed inclaim 1, wherein a second capillary structure is disposed on inner wallface of the tubular body, the second capillary structure being selectedfrom a group consisting of sintered powder body and a structure withmultiple channels.
 6. The thin heat pipe structure as claimed in claim1, further comprising a first capillary structure disposed in thereceiving space to enclose the support body.
 7. The thin heat pipestructure as claimed in claim 1, wherein the support body is selectedfrom a group consisting of mesh body, board material havingrecessed/raised sections on its surface and waved board body.
 8. Thethin heat pipe structure as claimed in claim 6, wherein the firstcapillary structure is attached to one side of the support body, thethin heat pipe structure further comprising a third capillary structuredisposed in the receiving space and attached to the other side of thesupport body opposite to the first capillary structure, the thirdcapillary structure being selected from a group consisting of sinteredpowder body, mesh body, fiber body and foam body.
 9. A manufacturingmethod of a thin heat pipe structure, comprising steps of: preparing atubular body and a support body; placing the support body into thetubular body; pressing the tubular body into a flat form; vacuuming thetubular body and filling a working fluid into the tubular body; andsealing the tubular body.
 10. The manufacturing method of the thin heatpipe structure as claimed in claim 9, further comprising a step ofpreparing a first capillary structure and fixedly attaching the firstcapillary structure to the support body before the step of placing thesupport body into the tubular body.
 11. The manufacturing method of thethin heat pipe structure as claimed in claim 9, further comprising astep of forming a second capillary structure in the tubular body afterthe step of preparing a tubular body and a support body.
 12. Themanufacturing method of the thin heat pipe structure as claimed in claim11, wherein the second capillary structure is selected from a groupconsisting of sintered powder body and a structure with multiplechannels.
 13. The manufacturing method of the thin heat pipe structureas claimed in claim 10, wherein the first capillary structure is fixedlyattached to the support body by means of a measure selected from a groupconsisting of spot welding, diffusion bonding and ultrasonic welding.14. The manufacturing method of the thin heat pipe structure as claimedin claim 9, wherein in the step of pressing the tubular body into a flatform, the tubular body is flattened by means of pressing.
 15. Themanufacturing method of the thin heat pipe structure as claimed in claim9, further comprising a step of bending the tubular body after the stepof placing the support body into the tubular body.
 16. The manufacturingmethod of the thin heat pipe structure as claimed in claim 9, whereinthe support body is selected from a group consisting of mesh body, boardmaterial having recessed/raised sections on its surface and waved boardbody.